The Chinese patent ZL03114505.1, entitled “a displacement mechanism for a compressor”, discloses a new type of displacement compressor with the advantages such as the absence of inlet valve and exhaust valve, a small number of moving parts, small vibration, high mechanical efficiency and reliable seal.
However, in the aforementioned patent, there exist implementation defects in design of the hinge structure where the piston is connected with the rotating disk. In the Chinese patent ZL03114505.1, there is a structure in which a piston pin seat is matched with a rotating disk pin seat and is connected therewith by a central pin to form cylindrical hinge joint. In such a structure, the piston pin seat has a convex structure lower at both sides and higher in a center thereof, with concave semi-cylindrical grooves at both sides and a convex semi-cylinder in the center; the rotating disk pin seat has a concave structure higher at both sides and lower in a center thereof, with convex semi-cylinders at both sides and a concave semi-cylindrical groove in the center; the convex piston pin seat and the concave rotating disk pin seat are embedded, and then connected with each other by the central pin being inserted into corresponding pin holes on the convex semi-cylinders thereof, thereby forming a cylindrical hinge with sealability penetrating a diameter of a spherical inner chamber of a cylinder (that is, a complete semi-cylindrical contact surface is formed between the facing semi-cylindrical groove and the semi-cylinder). However, for the aforementioned concave pin seat, it is difficult to process the concave semi-cylindrical groove in the center to be a complete semi-cylindrical surface capable of forming seal fit with the corresponding semi-cylinder due to its special structure. Such a structure is not suitable for mass production and cannot ensure accuracy, thereby influencing seal efficiency and overall performance. In another structure, there does not exist any center pin, a “C”-shaped hinge column sleeve with an opening formed on the rotating disk less than 180 degrees and a “Ω”-shaped cylindrical rotating shaft formed on the piston form cylindrical hinge joint, which has the function of hinge joint to some extent, but this kind of structure is poor in load carrying, is apt to be deformed when there is high pressure gas in the cylinder, causes sealing failure and will increase mechanical friction at other parts.
As such, with years of related experience in design and manufacture, the inventor proposes an automatic compensation mechanism for hinge seal gap in spherical compressor to overcome the defects in the prior art.